From patchwork Fri Oct 8 12:49:49 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lorenzo Bianconi X-Patchwork-Id: 12545293 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4A433C433F5 for ; Fri, 8 Oct 2021 12:51:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 33F6560EC0 for ; Fri, 8 Oct 2021 12:51:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242273AbhJHMxp (ORCPT ); Fri, 8 Oct 2021 08:53:45 -0400 Received: from mail.kernel.org ([198.145.29.99]:50352 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242155AbhJHMxk (ORCPT ); Fri, 8 Oct 2021 08:53:40 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 86A3C61037; Fri, 8 Oct 2021 12:51:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1633697504; bh=xrLgmj7H1KaMLgDfiwwj8AtxMVxiwz9rsEkykXo/wkw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=oOu2rOxkTHl8L7vJwCHflfb++aWa9pR9rHgYDdtfEAea9l6GIVOd291rQtJ2yCoo1 Rqb4MAqYxxl9uI6LK6KXbOTOsSHOaD4z5lvBg6m8d5UgF6/x1Bjs/CCnFoBclI/laM JolLQSD19alQKzh6x1RvE7pEFIWbhHVVgGZO0Uqa29B+Vyp4dihJMijzMQD0pQ1/bf +RT5+UrC6x5vJ4IMdgDov9MsYb09al4Ik4Cf/9LuHz7F6zXAzT2LEZOa/tt3y1IbDI Kb7vuLgx8dA1fGfBGo04AEI08VRAMCqP+5RUXBVsiIx5H2PxxA1fBGMqOW/RSUUHcB s19EXXgTwuvRA== From: Lorenzo Bianconi To: bpf@vger.kernel.org, netdev@vger.kernel.org Cc: lorenzo.bianconi@redhat.com, davem@davemloft.net, kuba@kernel.org, ast@kernel.org, daniel@iogearbox.net, shayagr@amazon.com, john.fastabend@gmail.com, dsahern@kernel.org, brouer@redhat.com, echaudro@redhat.com, jasowang@redhat.com, alexander.duyck@gmail.com, saeed@kernel.org, maciej.fijalkowski@intel.com, magnus.karlsson@intel.com, tirthendu.sarkar@intel.com, toke@redhat.com Subject: [PATCH v15 bpf-next 11/18] bpf: introduce bpf_xdp_get_buff_len helper Date: Fri, 8 Oct 2021 14:49:49 +0200 Message-Id: <6537553aa125a3d40b5ace41683109295a226ff2.1633697183.git.lorenzo@kernel.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Introduce bpf_xdp_get_buff_len helper in order to return the xdp buffer total size (linear and paged area) Acked-by: John Fastabend Signed-off-by: Lorenzo Bianconi --- include/uapi/linux/bpf.h | 7 +++++++ net/core/filter.c | 23 +++++++++++++++++++++++ tools/include/uapi/linux/bpf.h | 7 +++++++ 3 files changed, 37 insertions(+) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 6fc59d61937a..a9946d860740 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -4909,6 +4909,12 @@ union bpf_attr { * Return * The number of bytes written to the buffer, or a negative error * in case of failure. + * + * u64 bpf_xdp_get_buff_len(struct xdp_buff *xdp_md) + * Description + * Get the total size of a given xdp buff (linear and paged area) + * Return + * The total size of a given xdp buffer. */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -5089,6 +5095,7 @@ union bpf_attr { FN(task_pt_regs), \ FN(get_branch_snapshot), \ FN(trace_vprintk), \ + FN(xdp_get_buff_len), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper diff --git a/net/core/filter.c b/net/core/filter.c index 02fc6aa8a7b6..1749374a3d04 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -3784,6 +3784,27 @@ static const struct bpf_func_proto sk_skb_change_head_proto = { .arg2_type = ARG_ANYTHING, .arg3_type = ARG_ANYTHING, }; + +BPF_CALL_1(bpf_xdp_get_buff_len, struct xdp_buff*, xdp) +{ + u64 len = xdp->data_end - xdp->data; + + if (unlikely(xdp_buff_is_mb(xdp))) { + struct skb_shared_info *sinfo; + + sinfo = xdp_get_shared_info_from_buff(xdp); + len += sinfo->xdp_frags_size; + } + return len; +} + +static const struct bpf_func_proto bpf_xdp_get_buff_len_proto = { + .func = bpf_xdp_get_buff_len, + .gpl_only = false, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, +}; + static unsigned long xdp_get_metalen(const struct xdp_buff *xdp) { return xdp_data_meta_unsupported(xdp) ? 0 : @@ -7536,6 +7557,8 @@ xdp_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) return &bpf_xdp_redirect_map_proto; case BPF_FUNC_xdp_adjust_tail: return &bpf_xdp_adjust_tail_proto; + case BPF_FUNC_xdp_get_buff_len: + return &bpf_xdp_get_buff_len_proto; case BPF_FUNC_fib_lookup: return &bpf_xdp_fib_lookup_proto; case BPF_FUNC_check_mtu: diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 6fc59d61937a..a9946d860740 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -4909,6 +4909,12 @@ union bpf_attr { * Return * The number of bytes written to the buffer, or a negative error * in case of failure. + * + * u64 bpf_xdp_get_buff_len(struct xdp_buff *xdp_md) + * Description + * Get the total size of a given xdp buff (linear and paged area) + * Return + * The total size of a given xdp buffer. */ #define __BPF_FUNC_MAPPER(FN) \ FN(unspec), \ @@ -5089,6 +5095,7 @@ union bpf_attr { FN(task_pt_regs), \ FN(get_branch_snapshot), \ FN(trace_vprintk), \ + FN(xdp_get_buff_len), \ /* */ /* integer value in 'imm' field of BPF_CALL instruction selects which helper